Prompted by an understanding of the prevailing conditions and needs in the developing countries regarding the safety of water supplies in rural communities, and the rampant enteric diseases, a pertinent study was launched by us on June 4, 1979. this study, involving a series of experiments carried out over a period of more than two years, aimed at assessing the feasibility of solar disinfection of small quantities of drinking water that would satisfy the daily needs of individuals or a family. These experiments essentially consisted of subjecting artificially contaminated water in small, transparent containers, 1 to 3 litres in capacity, to direct sunlight for varying periods of exposure. The highly encouraging results of the numerous experiments demonstrated repeatedly the destructive effect of sunlight on pathogenic and non-pathogenic organisms.